Method of metallic arc welding



Sept. 20-, 1927. 1,643,227

'R.s1 REsAu METHOD OF MET'ALLIC ARC WELDING Filed Nov. 24 1924 INVENTOR.

' law/Mk0 $7715.51

IY/T/YESSI BY;

V1 4 Pa Mew 44. ATTORNEYS: I

4o lar form as before,

i so coupling,

' the side walls 'of'the channel. Excel Patented Sept. 20,1927. UNITED STATES RICHARD BTB-EBAU, OI WAUWATOSA, WISCONSIN, ASSIGNOB TO A. O. SMITH CORPORA- TION, OI IILWAUKEE, WISCONSIN, A CORPORATION OF NEW YORK.

METHOD OF METALLIC ABC WELDING.

Application and Hovember 24,1924. Serial ll'o. 752,027.

- The present invention relates to an improvement in the art of metallic arc weldmg, and it is particularly applicable to the production of pipe couplings of large diamo eter, which ordinarily are constructed of metal plates of excessive thickness. In forming such pi couplings b electric welding, it is expe lent, from t e manufacturing 1 standpoint, to take a thick metal plate of a length which will enable it to be bent or rolled into annular form with its ends in so as to produce a coupling of the csired diameter. The joining of the meeting ends of the thick plate by electric welding, so as to produce an integral structure in which the welded joint may be depended upon to possess a degree of strength which atleast is as great as that of the material of the coupling in which the joint is formed, is attended-with some difliculty. I have made many experiments along this line in attempts-to so ve the problems involved, and have found that the most satisfactory method of forming the welded 'oint is to first form a weldmg groove in t e line of the meeting ends of the plate so asto efiect a reduction in the thickness of that portion of the/metal which lies at the bottom of the groove, whereby the depth of penetration by the heat is lessened, and so that complete fusion in the lowermost stratum of the metal ma take place. I thus form the foundation or the uilding up of the uniformly welded o1nt by the application of successive layers of fused welding material.

Instead of scar-ting or chamferin the edges of the plate at their meeting en s aecording to the usual practice of forming the welding groove, I roll the strip into annubut with. the ends thereof a substantial distance apart, leaving an open gap, the dimensions of which will be determined by the size of'the coupllngand the thickness of the plate from which it is formed. In the welding channel thus.

formed I place a thin welding strip, the width of which approximates that of the channel the base or lower side of'the strip being liush with the inner surface of the and the edges of the strip abuts lent results have been achieved by the use of a strip which is triangular in cross section, such a construction presenting a strip havto ing the neeessary thin abutting edges with' roximitya central ridge at its upper side, which latter feature 0 constructlon will serve to revent warping of the stri' by the heat w en the electric arc is applie thereto. The are is caused to pla in t e an les formed at the 00 bottom of the c annel by t e junction of the" sides of the welding strip and the ends of the metal slate from which the coupling is" formed. pen the application of the arc, the thin edges of the metal strip and the '05 metal in the side walls of the channel are fused by the arc in such a degree that the somewhat ephemeral welding strip and the coupling blank are united into an integral structure b amalgamation of the metals. The we ding current is conducted bymeans of a fusible weldrod, which is fed to the work in the ratio of the consumption the welding channel, so that the arc will play across the welding strip and .upon both of the meeting ends of the. blank by-which the channel is formed. The operation is continued until the channel has been filled and the contour of the coupling is com------ pleted. Additional weldin metal in the orm of slu may be place in the channel, 5"- to befused y the electric arc, and thus hasten completion of the work. I The details of my invention will be hereinafter particularly described, and; the novelty thereof will be pointed out in the apoo' pended claims.

In the accompanying drawing:

Figure v1 is a perspective view of a pipe coupling arranged for the commencement of the weldin operation. as

Fig. 2 is a ragmentary view in elevation of one end thereof, and indicating the lateral vibration of the weldrod acrossthe welding strip.

Fig. 3-is a like fragmentary view showing the completely welded join 1 In the. drawing, the numeral 10 indicates a. mandrel or chill, curved across its upper. surface to the radius of the bore of the coupling,van d recessed longitudinally upon such curved surface so as to receive and retain during the welding o oration a backing strip-11. The coupling lank is indicated 12 and is drawn into the annular. shape shown from .a thick metal plate, the meeting ends'nfl prefera l mandrel, and a reducible welding strip 14' is then arranged in the channel, the said strip 14 resting at its base upon the backing strip llcarried by the mandrel. The

width of the welding strip 14 should be such as to cause its said edges to contact with the side walls of the channel and form a temporary bottom therefora As hereinbefore stated, the strip 14 is produced with thin ed es or sides and is conveniently and v of which 15 low, thereby forming a rib which will impart rigidity to the strip and obviate liability to warping or displacement under the heat of the electric arc during the welding operation.

The are lays in the angles formed by the edges 0 the welding strip and the adjacent walls of the channel, and by lateral.

vibration ofthe weldrod the arc is caused to cross from side to side over the welding strip so as to fuse the metals in and adjacent the paths of its movement. In addi tion, there -is a relative traverse of the weldrodand the work longitudinally of the latter, so that complete fusion is effected throughout the len h of the coupling. The fusion of the wel ing strip and the adjacent walls of the channel is supplemented by the fusion of the weldrod, so that a layer of metal, to which the weldrod contributes a portion, is formed with each longitudinal traverse of the-weldrod. This action is repeated, so that by successive layers the channel is filled and the contour of the coupling restored. To lessen weldrod consumption and hasten the welding operation,

additional welding material in the form -of slugs or strips may be placed in the channel for fusion by the arc.

While I have shown the welding strip as of triangular cross section, it is obvious that welding strips of other cross sections may be used, the essential feature being the arrangement of a thin edged convertible welding strip in the gap or channel of the coupling so as to ermit the arc to play in the angle and e ect ready and com lete fusion by. the arc of the metals in the lines of their contact. By the last term I mean that the welding action shall extend throu h to the bottom of the work at the angles. t is also desirable that the said strip be provided upon its upper face with a rigidifying formed as a-triangle, the apex.

rib, for the purposedescribed, but in whatever may be its form, the strip should have thin edges to permit penetration of thefusing current, and a central portion presenting 'sufiicient metal to resist destruction of the strip in the fusing action.

I have found the use of an impermanent backing strip 11 in connection with the mandrelto be a desirable expedient, inasmuch as the fusion of the edges of the welding strip may be to suchan extent that the backing strip will be caused to adhere to the coupling. Without such backing strip, the couplin would sometimes be welded to the mandre and difficulties would be encountered in effecting itsdetachment. The rovision of the backing strip and its use in the manner described eliminates this objection-' able condition and simplifies the operations performed in handling and treating the couplinfg.

I at the completion of the welding operation, the backing strip be found to have adhered to the coupling, such strip may be as the parts to be welded are always arran (1 in the same plane, be it curved or straight.

Having thus described my invention, what I claim and desire to secure by Letters Patent of the United States, is:

1. The method of arc welding which-comprises the formation of a thick metal plate into an annulus with the ends of the plate meeting in the same plane and spaced to form a welding channel, inserting a thin strip of welding metal and flush with the innervwall of the annulus to close the bottom of the said channel, and fusing the thin metal strip and the side walls of the channel into an integral structure by an electric arc.

2. The method of arc weldin prises the formation of a thic into an annulus with the ends of the plate meeting in the same plane and spaced to form a welding channel, insertin a thin strip of welding metal and flush wit the inner wall of the annulus to close the bottom of the said channel, conductin an arcing current b a fusible weldrod to use the thin metal strlp and the side walls of the channel, and filling the channel with welding metal flowing from, the weldrod to form an integral structure.

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which comp metal plate meager l 8.;

prises the formation of a. thick metal plateinto an annulus with the ends of the plate meeting in the same plane and spaced to form a welding channel, inserting a strip of welding metal of triangular cross section with its base at the'bott'om of the channel and 'flush with the inner wall of the annu- Ins, and fusing the said metal strip and the -side walls of the channel into an integral v structure by an electric are.

5. The method of arc welding which cumprises the formation of a thick metal plate I so into an annulus with the ends of the plate meeting in the same plane and spaced to form a welding channel inserting a strip of weldin metal provided with a rigidifymg rib in t e channel at the bottom thereof and flush-with the inner wall of the annulus to close the same, conductin an arcing current by 'a'fusible weldrod, an vibrating the arc across the said metal strip to fuse the latter and the side walls of thechannel to form "a thin edge an integral structure.

6. The method of arc welding which comprises the formation of a thick metal plate into an annulus with the ends of the plate meetingin the'same plane and spaced to form' a welding channel, arranging the annulus upon a mandrel with a temporary backing strip under the channel, inserting strip of welding metal in the bottom of the channelwith its base uponthe backing strip and flush with the inner wall of the annulus and fusing the welding strip and the; side wallsof the channel into an integral structure by an electric arc.

H a thin ed bottom 0 the channel with itsbase upon:

7. The method of arc-welding which comprises the formation of a thick metal plate into an annulus with the ends of the plate meeting in the same plane and spaced to form a weldingchannel, arranging. the annnlus upon a mandrel with a temporary backing stri underthe channel, inserting (i strip of welding metal in the the backin strip'and flush with the. inner wall of t e annulus, fusin the welding 9 strip and the sidewalls of t e channel b a current conducted by a fusible weldro and filling the channel with welding metal flowing from the'weldred to form an integral. structure.

8 The method of arc welding which con-'- sists in the formation of a thick metal plate into an annulus with the ends of'the plate meeting inthe same plane and separated to form the walls of a welding channel, inserting a thin edged strip of weldin material in the bottom of the channel and flush with the inner wall of the annulus, conducting an arcing current by means of a fusible weldrod, vibrating the weldrod across the weldin stri to unite the edges thereof to the si e wa s of the channel, and traversing the weldrod longitudinally ofthe channel to fill the same with welding metal flowing from the weldrod.

9. The method'of arc'welding which consists in the formationof athick metal plate with squared ends into an annulus in which such ends meet in the same'plane and stand.

segarated to form a welding channel with en stantially vertical side walls, inserting a triangular metal strip at the bottom of the said "channel to lie flush with and close the latter, conducting an arcing current into the channel byhneans of a fusible weldrod, vibrating the weldrod across the channel to fuse the welding strip and the side walls of the channel into a weld, and traversing the-weldrod longitudinally of the channe to fill the same with weldin material flow-' ing from the weldrod an complete the Welded joint. 10. The method of arc welding which consists inarranging thick metal plate edges in the same lane and spaced apart to constitute a we ding channel, inserting a thin;

edged strip at the bottom of the channel to lie flush with and close the latter, and fusing the said strip and plate edges forming the channel into an integral structure byan electric are.

11.. The method of arc welding which eonsists in arranging squared thick metal plate edges in the same planeso as to form a I welding channel having substantially vertical side walls, inserting a thin edged metal stri flusii the said strip and the plate edges forming the channel mto an integral structure by an electric arc.

' 12. The method of arc welding which consists in arranging squared thick metal plate edges in the same lane so as to form a weld-- ing channel havlng substantially vertical at the bottom of the channel to lie with andclose the latter, and fusing side walls, inserting a thin edged metal strip 1 at the bottom of the channel to lie flush wi and close the latter, conducting a welding current by means of a fusible weldrod, andfusing the said strip and the plate edges forming the channel into anintegral structure, by an electric arc. a

13. The method of arc welding which consists in arranging squared thick metal plate ed es in the same plane so asto form a welding channel having substantially vertical side walls insertin a thin edged metal channel with additional welding metal fl0wstrifi at the hottom o the channel to lie in :from the fusible weldrod.

flus with and close the latter, conducting n testimony whereof, I have signed my 10 a welding current by means of a fusible name at Milwaukee, this 21st day of Novem- -'weldr0d, using the said strip and the plate ber, 1924.

edges forming the channel into an integral structure by an electric arc, and filling the R. STRESAU. 

